WITH two current cases of Cucumber Green Mottle Mosaic Virus in Queensland, industry and the Queensland Department of Agriculture and Fisheries (QDAF) are continuing to raise the profile of the rapid virus.

At an Australian Melon Association industry update meeting in Ayr in August, QDAF addressed growers, agronomists and industry body groups about protecting the industry and minimising impacts of CGMMV.

CGMMV is a virus that infects plants with members of the melon or cucurbit family being most susceptible. This virus does not affect humans or animals but is easily spread by contact including leaves making contact or brushing against infected plants as equipment or people move along rows.

The virus causes a range of symptoms on leaves but the biggest issue with watermelon is that fruit may look normal on the outside but the flesh begins to breakdown and may only be seen when fruit arrives at the market.

The virus has been known for decades overseas but the has spread rapidly in the last five to 10 years and now occurs in most countries, including Australia.

QDAF Principal Plant Pathologist Denis Persley.

BQ Principal Plant Pathologist, Denis Persley, said the virus was first found in Australia in 2014 in watermelon crops in the Northern Territory.

“It is thought that low levels of transmission through seeds of watermelon, cucumber and some other cucurbit types have been largely responsible for this rapid international spread,” he said.

“Today there are two cases of CGMMV in Queensland.

“The virus is in a cucumber greenhouse production area at Bundaberg and in an isolated melon production farm in North Queensland.​

“The Bundaberg outbreak was detected this year, while the North Queensland outbreak was first detected in 2015.

“All these outbreaks are being managed to minimise losses and reduce virus levels as far as possible.

“All cases are regarded as serious because of the potential economic losses to growers and the risk of further spread.”

An outbreak of CGMMV is a high priority for QDAF as it has potential dramatic effect on yield, fruit quality and the agricultural industry.

“The capacity for rapid spread in crops is important. Most plant viruses need living plants to survive but CGMMV on the other hand can survive in soil/crop debris and surfaces such cutting knives for periods of over 12 months.

“This means infested land may be unable to be used for cucurbit production for at least for one to two years.

“Also a concern is the chance of introduction to production nursery/ farm via infected seed used for planting.”

To this day the largest and most damaging outbreak was the initial outbreak in the Northern Territory, particularly around Katherine in field grown watermelon crops.

Losses of many millions of dollars were sustained through loss of crops through destruction, quarantines on fruit movement and property quarantines for two years on melon production.

To prevent another catastrophic outbreak, Department of Agriculture and Fisheries and Biosecurity Queensland have several procedures in place.

Biosecurity Queensland and Department of Agriculture and Fisheries discuss CGMMV at an industry meeting in Ayr.

“In Queensland, DAF through Biosecurity Queensland have made regular surveys to determine if the virus is present in the important cucurbit production areas around Bundaberg, Ayr, and southern Queensland,” Mr Persley said.

“DAF is also working closely with affected growers to help them better understand the virus, implement practical management measures, and to contain the spread of the virus.

“All known infested properties have been declared as ‘restricted places’ under the Biosecurity Act 2014 and although the property owners are still able to trade, they must adhere to specific biosecurity measures designed to minimise the spread of the disease from those properties.

“All cucurbit seed lots for planting in Australia are tested for CGMMV before release at a level higher than formally recommended by international seed testing authorities.”